ARM: dts: omap3-beagle-xm: fix string error in compatible property

The beagle and beagle-xm entries were inside the same double quote.
Split them to have two distinct entries.
Signed-off-by: Robert Nelson <robertcnelson@gmail.com>
Signed-off-by: Benoit Cousson <bcousson@baylibre.com>

arch/arm/boot/dts/omap3-beagle-xm.dts

@@ -11,7 +11,7 @@
 
 / {
 	model = "TI OMAP3 BeagleBoard xM";
-	compatible = "ti,omap3-beagle-xm, ti,omap3-beagle", "ti,omap3";
+	compatible = "ti,omap3-beagle-xm", "ti,omap3-beagle", "ti,omap3";
 
 	cpus {
 		cpu@0 {